mmc: sdhci-esdhc-imx: add card detect on custom GPIO for mx25/35

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Marc Reilly <marc@cpdesign.com.au>
Tested-by: Eric Benard <eric@eukrea.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 79 insertions, 0 deletions

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 49c9801ef122..3b5248567973 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -32,6 +32,39 @@ static inline void esdhc_clrset_le(struct sdhci_host *host, u32 mask, u32 val, i
         writel(((readl(base) & ~(mask << shift)) | (val << shift)), base);
 }
 
+static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
+{
+        /* fake CARD_PRESENT flag on mx25/35 */
+        u32 val = readl(host->ioaddr + reg);
+
+        if (unlikely(reg == SDHCI_PRESENT_STATE)) {
+                struct esdhc_platform_data *boarddata =
+                                host->mmc->parent->platform_data;
+
+                if (boarddata && gpio_is_valid(boarddata->cd_gpio)
+                                && gpio_get_value(boarddata->cd_gpio))
+                        /* no card, if a valid gpio says so... */
+                        val &= SDHCI_CARD_PRESENT;
+                else
+                        /* ... in all other cases assume card is present */
+                        val |= SDHCI_CARD_PRESENT;
+        }
+
+        return val;
+}
+
+static void esdhc_writel_le(struct sdhci_host *host, u32 val, int reg)
+{
+        if (unlikely(reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE))
+                /*
+                 * these interrupts won't work with a custom card_detect gpio
+                 * (only applied to mx25/35)
+                 */
+                val &= ~(SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT);
+
+        writel(val, host->ioaddr + reg);
+}
+
 static u16 esdhc_readw_le(struct sdhci_host *host, int reg)
 {
         if (unlikely(reg == SDHCI_HOST_VERSION))
@@ -121,6 +154,14 @@ static struct sdhci_ops sdhci_esdhc_ops = {
         .get_min_clock = esdhc_pltfm_get_min_clock,
 };
 
+static irqreturn_t cd_irq(int irq, void *data)
+{
+        struct sdhci_host *sdhost = (struct sdhci_host *)data;
+
+        tasklet_schedule(&sdhost->card_tasklet);
+        return IRQ_HANDLED;
+};
+
 static int esdhc_pltfm_init(struct sdhci_host *host, struct sdhci_pltfm_data *pdata)
 {
         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
@@ -153,9 +194,40 @@ static int esdhc_pltfm_init(struct sdhci_host *host, struct sdhci_pltfm_data *pd
                                 "no write-protect pin available!\n");
                         boarddata->wp_gpio = err;
                 }
+
+                err = gpio_request_one(boarddata->cd_gpio, GPIOF_IN, "ESDHC_CD");
+                if (err) {
+                        dev_warn(mmc_dev(host->mmc),
+                                "no card-detect pin available!\n");
+                        goto no_card_detect_pin;
+                }
+
+                /* i.MX5x has issues to be researched */
+                if (!cpu_is_mx25() && !cpu_is_mx35())
+                        goto not_supported;
+
+                err = request_irq(gpio_to_irq(boarddata->cd_gpio), cd_irq,
+                                 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+                                 mmc_hostname(host->mmc), host);
+                if (err) {
+                        dev_warn(mmc_dev(host->mmc), "request irq error\n");
+                        goto no_card_detect_irq;
+                }
+
+                sdhci_esdhc_ops.write_l = esdhc_writel_le;
+                sdhci_esdhc_ops.read_l = esdhc_readl_le;
+                /* Now we have a working card_detect again */
+                host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;
         }
 
         return 0;
+
+ no_card_detect_irq:
+        gpio_free(boarddata->cd_gpio);
+ no_card_detect_pin:
+        boarddata->cd_gpio = err;
+ not_supported:
+        return 0;
 }
 
 static void esdhc_pltfm_exit(struct sdhci_host *host)
@@ -166,6 +238,13 @@ static void esdhc_pltfm_exit(struct sdhci_host *host)
         if (boarddata && gpio_is_valid(boarddata->wp_gpio))
                 gpio_free(boarddata->wp_gpio);
 
+        if (boarddata && gpio_is_valid(boarddata->cd_gpio)) {
+                gpio_free(boarddata->cd_gpio);
+
+                if (!(host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION))
+                        free_irq(gpio_to_irq(boarddata->cd_gpio), host);
+        }
+
         clk_disable(pltfm_host->clk);
         clk_put(pltfm_host->clk);
 }